NATO member states which are not fulfilling their financial obligations to the US-led military bloc will be “dealt with,” Donald Trump has warned, particularly singling out Germany as a country not contributing enough.

The veiled threat came at a cabinet meeting in Washington on Thursday, which was attended by NATO’s secretary general, Jens Stoltenberg.

“We have some that don’t [provide a sufficient contribution to NATO] and, well, they’ll be dealt with,” Trump said, as cited by Reuters. Berlin, in particular, “has not contributed what it should be contributing and it’s a very big beneficiary,” he told Stoltenberg.

“It is impacting allies because now all allies are increasing defense spending. No allies are cutting their budgets anymore,” the NATO chief said.

However, not everybody is willing or capable of enlarging their defense budgets to the ‘minimum’ level of 2 percent of gross domestic product by 2025, as demanded by Trump.

German Defense Minister Ursula von der Leyen said on Monday that the country will only increase its military spending by 1.5 percent in the next seven years. Von der Leyen said that money shouldn’t be the main criterion and noted that Germany remains the second-largest contributor of manpower to NATO. The statement was somewhat surprising as it was made just hours after Chancellor Angela Merkel promised that Germany will stand by its 2 percent pledge to the alliance.

“We look forward to the German government bringing a credible plan to the July NATO summit showing how it will meet its pledge to spend 2 percent of GDP on defense,” Richard Grenell, the new US ambassador to Germany, told Bloomberg in an emailed response on Thursday.

Relations between the US and Germany are currently marred by several issues besides defense spending. Berlin is leading the EU’s resistance to US tariffs on steel and aluminum, while Washington is pressuring Germany to give up on the construction of the Nord Stream 2 natural gas pipeline from Russia.

The American pullout from the Iranian nuclear deal was also condemned by the German leadership. “It’s no longer the case that the US will simply just protect us. Europe needs to take its fate into its own hands,” Merkel said shortly after Trump’s decision to withdraw from the landmark deal, which is universally backed in the EU.

Trump was critical of NATO during his campaign for the White House, repeatedly calling the bloc “obsolete” and too costly for US taxpayers to maintain. However, after assuming office, the US leader has made a U-turn in his views, pledging full American support to the alliance. “I said it was obsolete. It's no longer obsolete,” he said, claiming that NATO has since shifted towards “fighting terrorism,” just as he wanted.